lib9p: update diroffset correctly on rewind
diff --git a/src/lib9p/srv.c b/src/lib9p/srv.c
index 7393b3c..0e7c311 100644
--- a/src/lib9p/srv.c
+++ b/src/lib9p/srv.c
@@ -505,7 +505,7 @@
 rread(Req *r, char *error)
 {
 	if(error==nil && (r->fid->qid.type&QTDIR))
-		r->fid->diroffset += r->ofcall.count;
+		r->fid->diroffset = r->ifcall.offset + r->ofcall.count;
 }
 
 static void